The present invention relates to the manufacture and design of notebook computers. Particularly, the present invention relates to using titanium or titanium alloys in the main and display housings of notebook computers.
Notebook computers generally have two main parts, a main housing and a display housing. The main housing typically contains the keyboard and cursor positioning device together with most of the hardware for operating the computer, while the display housing, rotatably hinged to the main housing, typically contains an LCD or other visual screen. Both the main and display housings are generally formed of strong, shock-resistant materials such as polycarbonate, carbon-fiber filled polycarbonate, or other materials suitable for injection molding. Because a notebook computer may be used in a laptop environment such as a train, a taxi cab, or an airliner where it may be dropped, knocked, battered, slapped, jolted, pummeled, smashed, pounded, hammered, or bumped, screws are typically used to fasten the component parts of the notebook computer""s main and display housings. Although screws supply needed structural strength, they often mar aesthetic appearances.
Making computer housings of plastic, polycarbonate, or other injection moldable materials furnishes computer housings that are lightweight and durable, easier to fabricate and assemble than computer housings made metals or other stalwart materials, such as titanium or titanium alloys, and inexpensively produced.
On the other hand, manufacturing computer housings of injection moldable materials often creates bland aesthetic appearances, produces computer housings that often shatter when dropped, often requires screwing component parts together, and often allows heat generated from the computer""s internal hardware to be transmitted directly through the main housing to a user""s lap or hands. If the computer is used for long periods, the warmth can become wholly unbearable. Because of these and other disadvantages, a previously unsatisfied need has existed for notebook computer housings that are manufactured mostly of a strong, lightweight, and heat-insulating material, like titanium or a titanium alloy. An aspect of the present invention that helps overcome the disadvantages associated with the prior art is the use of titanium in the computer housings.
Titanium is appreciated in many arts for its lightness, strength, durability, and non-magnetic properties. Additionally, titanium can be formed into thin sheets that can be both strong light. Titanium and its alloys, however, are not currently used to manufacture notebook computer housings because it is very difficult to fabricate titanium and very difficult to join titanium securely to non-titanium materials such as polycarbonate. In fact, titanium can only be fabricated using special tools and processing methods, which include, inter alia: casting, hot working (forging, extrusion, rolling, superplastic forming, diffusion bonding), cutting, machining, milling, turning, drilling, chemical milling, welding, and superplastic forming. Additionally, titanium and titanium alloys can be cut by conventional band saws, torches, water jets, and lasers. Moreover, special tools and methods are required to place screw holes in titanium metal or titanium alloys. Exemplary tools and methods include: reaming with standard carbide and high speed steel reamers, drilling with lasers, and broaching with wet and dry broach tools.
As mentioned above, it is very difficult to join titanium to non-titanium materials such as polycarbonate. For example, fusion welding, resistance welding, and similar welding methods can be used to join titanium and its weldable alloys, but such methods are not suitable for joining titanium to other materials. Instead, titanium is often fastened to other materials using mechanical fasteners (e.g. screws, rivets, etc.), friction welding, brazing, and explosive bonding. Titanium is not typically used to fabricate housings for laptop computers because it is difficult to form fittings or other details into titanium. Without details and fittings, the titanium is difficult to connect to other materials to form an enclosure. In one instance, a titanium exterior shell has been secured by screws to a plastic cover of a display housing. One reason that screws are used is that the user (or a repairman) needs to be able to access the internal elements in the enclosure of the laptop.
Gluing two components together is well known in the art. However, computer housings were not glued together for several reasons. It was commonly thought and taught in the art that housings whose components were glued together would be weak and easily breakable. Moreover, it was thought that a glued computer housing precluded the ability to repair or replace items contained within the case. In spite of such thoughts and teachings, embodiments of the present invention provide for gluing titanium sheet metal to polycarbonate components, or to components made of a similar material, to form computer housings that are strong, lightweight, durable, aesthetically pleasing, and internally-accessible.
An embodiment of the present invention includes a laptop computer that has a display housing and a main housing. The main housing is rotatably coupled to the display housing. At least the case of the main housing comprises titanium.